1. Field of the Invention
The present invention relates to a method for assessing data worth for analyzing yield rate, and more particularly to a method for processing measured data corresponding to semiconductor manufacturing and assessing data worth for analyzing yield rate.
2. Description of Related Art
For controlling stable manufacturing and production quality, semiconductor manufacturers always record related production information during manufacturing. Since semiconductor manufacture is very complicated and production ability always needs to be maximized, the amount of recorded data is quite large. Once abnormal conditions occur, analysts must firstly determine control factors, time ranges, and data units for test when they want to select factors affecting changes of yield rate from huge databases.
The selection of control variables has a great influence on analysis results. Whether effective analysis results can be obtained depends on whether or not data sets for analysis include information regarding changing factors affecting yield rate. Because there are a lot of control variables, composite factors affecting changes of yield rate usually cannot be picked out totally based on analysts' experience. Furthermore, if the selection of data units causes information loss (for example, average values cannot reflect changes of average data), data sets for analysis do not include information about changing factors affecting yield rate. Accordingly, if the validity of data sets is not judged firstly, then the reliability of analysis results cannot be measured.
Hence, the inventors of the present invention believe that the shortcomings described above are able to be improved and finally suggest the present invention which is of a reasonable design and is an effective improvement based on deep research and thought.